Fault-tolerant Control of a Novel Powered Wheelchair Driven by Rim Motors with Hall Effect Sensors

摘要

This paper discusses the fault-tolerant control of a novel powered wheelchair driven by rim motors. This rim motor is a permanent magnet synchronous motor (PMSM) that is controlled by measuring rotor angles using three Hall effect sensors. A failure of any one of the Hall effect sensors causes false detection of the rotor position, thereby deteriorating the control performance of the motor. The proposed control strategy allows accurate estimation of rotor position even if one or two of the three Hall effect sensors malfunction. When all the three sensors on any rim motor fail, a sensorless control is activated. The fault-tolerant control strategy is proved by experiments and makes the novel powered wheelchair safer and more reliable.